A so-called “conductive paste” with a large amount of a particulate silver flakes, copper powder, or carbon particles mixed in a resin or an adhesive has come into practical use. Many of polymer-type conductive pastes put into practical use form a pattern by a screen printing method and heating and curing the pattern to form a conductive pattern (see Japanese Patent Publication No. 2654066 and Japanese Patent Laid-open Publication No. 2005-267859), but it is difficult to accurately draw a fine pattern.
Thus, to enhance fineness of a pattern, a conductive paste capable of being etched (Japanese Patent Laid-open Publication No. 10-064333) has been developed and, further, a photosensitive paste that forms a conductive pattern has been developed which is capable of exhibiting conductivity at a relatively low temperature and which is capable of forming an organic-inorganic composite conductive pattern having a low resistivity on a flexible substrate such as a film (Japanese Patent Laid-open Publication No. 2011-180580).
However, to form a pattern by a photolithography method using the conventional conductive paste capable of being etched, further, a resist layer must be formed on a coating film of the conductive paste, leading to the problem that the production process of a conductive pattern is complicated. The conventional photosensitive paste that forms a conductive pattern often contains excessive ion components derived from a raw material of the paste or generated or mixed during production of a conductive pattern, and there are the problems that materials such as a substrate are degraded, and that adhesion of the produced conductive film to the substrate is reduced.
Thus, it could be helpful to provide a photosensitive conductive paste capable of fine patterning and exhibition of conductivity at a low temperature without adversely affecting materials such as a substrate, and also capable of forming a conductive pattern having a low resistivity and excellent adhesion to the substrate; and a method of producing a conductive pattern using the photosensitive conductive paste.